In general, powdery or granular food such as instant coffee is sold in a state where the food is packaged in a high-hermetically sealed packaging container such as a capped bottle so as to maintain a sealed state during storage or the like. As such a packaging container, a packaging container, for refilling, which can facilitate transfer of contents is suggested in Patent Literature 1. When the contents are transferred from the packaging container to a storage container or the like, the packaging container is opened and put in an opening portion of the storage container, to gradually transfer the contents.
The packaging container disclosed in Patent Literature 1 includes a cylindrical container body, a funnel component, a sealing lid, and a covering cap. The funnel component includes a funnel portion, and a side wall portion connected with an end portion, on a wide opening side, of the funnel portion. The side wall portion is fitted into the container body, and joined to an inner surface of the container body. The funnel portion has such a shape as to reduce its diameter toward an outer side of an opening portion of the container body. Further, an edge, on a narrow opening side, of the funnel portion and an edge of an open end of the container body are coplanar with each other. The container body is filled with contents, and the edge of the open end of the container body is sealed with the sealing lid. In the sealing lid, a plurality of perforation lines are formed so as to extend radially from the center of the sealing lid. Further, the covering cap for covering the top of the sealing lid during storage, circulation, or the like is mounted to prevent the sealing lid from being cut.
When contents in the packaging container are transferred for refilling, the covering cap is removed from the packaging container, and the sealing lid is put and pressed into an opening of a case to be refilled with the contents. Thus, the sealing lid is cut along the perforation lines, whereby the contents can be easily transferred through the funnel component.
In the packaging container, since sealing between the funnel component and a membrane is not performed, a problem arises that the contents are moved onto the outer side of the funnel component through a gap between the funnel component and the membrane during transportation or the like. In a case where the contents are transferred from a package for refilling to a storage container or the like in a state where the contents have been moved onto the outer side of the funnel component, the contents having been moved onto the outer side of the funnel component are not transferred to a case, such as the storage container, to be refilled, and may scatter (externally) on the outside of the case to be refilled. Therefore, the contents are spilled on/around a refilling work space such as a table, and clearing such as cleaning is necessary. Therefore, in Patent Literature 3, it is suggested that an end portion, on a narrow opening side, of the funnel component projects outward of an open end of the container body such that the membrane and the end portion, on the narrow opening side, of the funnel component are maintained so as to be in close contact with each other, thereby preventing the movement of the contents (see, for example, FIG. 9 of Patent Literature 3).
Such a packaging container may be subjected to an environment where air pressure inside the packaging container becomes different from air pressure outside the packaging container during circulation. In a case where, for example, packaging containers that are filled with contents in summer in which the temperature is high are in shops in winder in which the temperature is low, air pressure inside the packaging containers is reduced relative to air pressure outside the packaging containers, and the side surface portions of the packaging containers are recessed toward the inside of the packaging containers. Therefore, a problem may arise that the design of the packaging containers is degraded. On the other hand, in a case where, for example, packaging containers that are filled with contents in a place such as a flat land in which the altitude is relatively low, are circulated and placed in a place in which the altitude is high, air pressure inside the packaging containers is increased relative to air pressure outside the packaging containers, and the side surface portions of the packaging containers expand outward of the packaging containers. Therefore, problems may arise that the design of the packaging containers is degraded and contents are ejected due to, for example, breakage caused by a small impact. In order to solve the problems, a container is suggested in which a laminated member of the side surface portion of the container is formed so as to be partially separable, and, particularly when an internal pressure is reduced, an inner layer of the laminated member is separated and expanded toward the inside of the container, to alleviate reduction of pressure in the container, thereby preventing the side surface portion of the container from being recessed (see, for example, Patent Literature 4).